1. Field of the Invention
This invention relates to maintaining properly synchronized data in an environment where data can be sent and received through separate pathways.
2. Description of the Related Art
Growth in the personal computing industry has given rise to the current day, where many people have multiple computing devices. It is not at all uncommon for a person to have a desktop computer, a laptop computer, and a mobile computing device such as a cell phone or personal digital assistant (PDA). Various computing devices fulfill different needs of the user. For example, a laptop may be a more comfortable platform for sending and typing email, but a cell phone (such as a smart phone) is often a more versatile email tool since it can use the service provider's wireless network to send and receive messages and, as a result, generally has broader availability. It is not at all uncommon for a user to have cell phone reception and corresponding email access but not have access to a network that the laptop can connect to.
The inconvenience of using a smart phone to send email is so prevalent that it has entered our cultural lexicon in the form of phrases such as “Blackberry thumb.” Lenovo's Constant Connect avoids these difficulties by allowing the user to use the laptop for sending email even when it is not connected to a network; Constant Connect uses the laptop's network when it is connected to a network, and communicates data from the laptop using the cell phone's connection when the laptop cannot directly communicate with a compatible network. While this solution provides a user with the ability to use the laptop for sending and receiving data regardless of the laptop's network connection, it causes difficulty in maintaining synchronized data.
The above, of course, is simply one example a situation where synchronization problems can arise because data can travel multiple pathways to and from a source. For example, in the case of an email client on a laptop, duplication can occur if the cell phone sends the message for the laptop but the laptop sends the message itself when it is later connected to a network. Similar problems can occur that cause emails to appear multiple times in the user's inbox on the laptop. Both inbound data and outbound data can be duplicated and show up in inboxes multiple times.
Data being sent and resent multiple times can cause difficulty and frustration for a user. If duplicate emails are regularly sent and received, the annoyance of manually tracking which emails actually did or did not get sent earlier, manually cleaning duplicates out of the inbox, and repeatedly explaining why certain messages were sent twice, could prevent many users from even making use of a system offering multiple pathways. And if the data is information such as software patches and updates, receiving additional copies of executables that have already run can generate difficulties on the receiving system such as errors and failed installs. At the very least, it introduces additional down time when the computer unnecessarily installs something that has already been installed.